...Oh! Bring business cards with your name and at least one way to get in touch with you. Even if they're cheapo pre-perforated cards that you print on your printer, that's fine. You're certain to meet people who you'll want to keep in contact with (or people who want to keep in contact with you), and a business card is a quick and easy way to transfer contact info.

Protospiel South is a place for games in all stages of development. If your game is completely playable, but needs you there to explain how to play it, that's perfectly fine. If you have rules that are good enough to run a "semi-blind" playtest, more power to you! Having short questionnaires for playtesters to fill out after (or while) playing is a great idea.

Really, my only expectations are that you:
* know why you're asking players to play your games
* take notes during and after your game is played so you can make use of player feedback
* play other designers' games (to give them good feedback and to expose yourself to other designers' designs).

Bring your game(s) and a good attitude and it'll all go well, I'm sure.